A mineral is a chemical
substance which is a
naturally occurring solid that
has not been made by
animal, plant or any other
type of organism.
common minerals are
haematite, bauxite, galena,
malachite, chalcopyrite,
rutile, cassiterite,
chromite, pentlandite and
opal
some minerals are
pure elements.eg.
silver and gold.
native copper is found as pure
copper. more commonly, copper is
found as an ore. three copper ores
are bornite, azurite and malachite.
Ores are rocks that
contain valuable
minerals like iron and
copper
main properties of
minerals are their:
hardness, lustre, colour,
streak colour, flame
colour
in flame tests, minerals are first ground
into powders or dissolved. some of the
poweres or dissolved mineral is then
put into a hot flame. the mineral glows
an gives the flame a charecteristic
colour that may then be used to
identify the mineral.
hardness is assessed by
comparing minerals using Mohs
scale.
colour is very useful when
prospecting for minerals. for
example, gold shows up as a
yellowish colour in rock and soil.
lustre is how shiny a mineral is.
lustre is divided into many
categories. examples are glassy,
waxy, metallic, dull.
streak is the colour left
behind when you try to
scratch and unglazed white
tile with the mineral.